Homework 5

Assigned: Mar. 3
Due: Mar. 24 [sic].

Problem 1

Consider a toy paging system. There are four frames and
six pages. In the sequence of events listed below, "Read I" means
that an address in page I must be read; "Write I" means that an address
in page I must be written to; "TICK" is a clock tick. (Keep in mind that
the arguments to Read and Write are
pages, not frames.) List the page faults that occur, and the frames chosen
for the new pages, if the OS uses (A) the Not Recently Used (NRU) PRA;
(B) the Second Chance PRA; (C) the aging PRA; (D) Belady's (optimal)
algorithm. If the algorithm gives a tie
between pages to replace, choose the one with the lower frame. Assume
that memory is initially empty.